ChatGPT examples: 210 real use cases with prompts

Carlos Mendoza's 4th-grade son marked only B and F as correct in a Santillana exercise on numbers up to the billions. The platform's solution marked B, D and F, but D said '9,615 rounded to the billions is 10,000', which is false. When Mendoza asked ChatGPT to review it, it first said Santillana was right, reading 'billions' as if it were 'thousands'. Only when Mendoza pointed to the exact word did ChatGPT acknowledge the error. The son had been right from the beginning.

ChatGPT · Personal · Source date: Oct 17, 2026

A Topretirements blogger's Medicare Part D drug plan wrote to say the 2027 premium would rise from $98.30 to $126 a month. They asked ChatGPT for cheaper options, giving their Florida ZIP code, their medications and preferred pharmacies. It suggested several, including a plan at $5.30 a month in their area, $1,448.40 a year less in premiums. They didn't switch on ChatGPT's word alone: as their insurance agent also advised, they checked it in Medicare's official Plan Finder, which confirmed the switch made sense, and enrolled. They get most prescriptions through the VA, so the cheapest premium suited them; they note others need to compare total yearly cost.

ChatGPT · Personal · Source date: Oct 16, 2026

Dave W Plummer missed an important appearance and asked the ChatGPT desktop app, which has access to their Gmail, to work out how it happened. It found Plummer had noon in mind, the time of an earlier prep call, while the event started at 7:50 a.m. Pacific, with emails also mentioning 8:50 a.m. Mountain. When Codex then reconstructed the email trail, it found the organiser had cancelled the calendar invite sent to Plummer's regular address while sorting out a Teams login mismatch, and the later confirmation email had no new invite. With Codex, Plummer then set up a recurring agent that reads email threads, including changes and cancellations, adds missing calendar entries with the source email and link, and flags contradictions. Test alerts at first didn't notify on the iPhone; after checking alarms, sync and Focus settings, a test finally rang. It now checks every ten minutes while the Mac is awake; its first historical review was still running.

ChatGPT, Codex · Personal · Source date: Oct 15, 2026

A small plastic tab broke on Michal Barodkin's Philips shaver after several years. Rather than replace the shaver, they sent ChatGPT a photo of the broken piece and described the problem in a voice message. It found the replacement part, with its Philips part number and a place to order it. It cost six dollars and they picked it up the next day.

ChatGPT · Shopping · Source date: Oct 7, 2026

Thy Toeung needed to review their car insurance before their son turned 16. They made a data sheet listing every driver, vehicle and the cover they wanted, and asked Claude, ChatGPT, Gemini and Muse to act as their insurance-shopping agent and get real quotes from six reputable insurers. Gemini's auto-browse explained it couldn't use the websites and handed back a comparison table to fill in. ChatGPT took 2 hours and 279 messages across 12 attempts and got no quotes; Toeung believes sites such as Allstate, Nationwide and Liberty Mutual block AI agents. Claude ran for 3.3 hours and got 5 real quotes. Muse, on its free tier, used several sub-agents and got 5 quotes in about 20 minutes. Toeung switched insurer and got about twice the cover for around 40% of the previous price.

Claude, ChatGPT, Gemini, Muse · Shopping · Source date: Oct 6, 2026

Gokul N.'s blood test results from Superpower took 20 days. Gokul asked ChatGPT to check the refund policy, look at the dates and email the concierge. The email cited Section 14(a) of the membership agreement, set out the timeline with Superpower's own support replies, asked them to confirm when results had actually been available, and added a fallback asking for an exception if a different policy applied. Two days later Superpower confirmed a full $199 membership refund.

ChatGPT · Personal · Source date: Sep 30, 2026

Mr Jasper's spouse needed a Tax ID, and the agent they contacted quoted 10k and asked for the spouse's NIN to process it the next day. Mr Jasper asked ChatGPT about it and how long it takes, and found it was something they could do themselves in a few minutes. They opened the official portal with the spouse's NIN and the Tax ID was ready in less than one minute, saving the 10k fee.

ChatGPT · Personal · Source date: Sep 21, 2026

Ary Aranguiz connected ChatGPT to Gmail and asked it to create four labels: ACTION/Reply, ACTION/Decision, ACTION/Review and STATUS/Waiting. ChatGPT then reviewed 204 unread emails from the past seven days and proposed which belonged under each label, separating people waiting for a reply, invitations needing a decision, information to review and routine mail needing no action. It noticed the original label set was incomplete and recommended adding ACTION/Review. Aranguiz approved the proposals, and only then did it create the label and apply the labels. It didn't send, delete, archive, forward or mark anything as read.

ChatGPT · Personal · Source date: Sep 4, 2026

mattmaroon runs a seasonal business and noticed their state unemployment insurance rate had jumped from 0.75% to 12.75%. Instead of hours on the state website and on hold, they asked ChatGPT what had happened. It worked out that they were being charged a penalty rate because their new payroll provider doesn't file wage reports for the one quarter with no wages, and without a report the business counted as delinquent. ChatGPT filed the correct wage report and went to the support site to request a retroactive rewrite, which was granted, saving many thousands of dollars without hitting the 5-hour usage limit.

ChatGPT · Ops · Source date: Aug 27, 2026

joenot443 was quoted $6k to fix their pool's plumbing and rebuilt it themselves over a few days with YouTube and GPT, for about $1k of materials. It was their first outdoor plumbing job and they'd never touched PVC. They say they wouldn't have had the confidence from YouTube alone: specific diagnostic help and a full diagram made the difference, and they had it prepare an SVG of the whole assembly with every measurement and part labelled.

ChatGPT · Personal · Source date: Aug 11, 2026